초록 ▼

A power supply circuit includes a booster circuit for boosting an output voltage from a power supply battery to predetermined positive and negative voltages, respectively. A main capacitor is charged by the predetermined positive or negative voltage boosted by the power supply circuit. In a discharg

A power supply circuit includes a booster circuit for boosting an output voltage from a power supply battery to predetermined positive and negative voltages, respectively. A main capacitor is charged by the predetermined positive or negative voltage boosted by the power supply circuit. In a discharge tube, a discharge current flows on the basis of the charge built up on the main capacitor, so that flash light emission is performed. A MOS controlled thyristor (MCT) is inserted in the loop of the discharge current from the main capacitor. A control circuit ON/OFF-controls the MCT by selectively applying the predetermined positive or negative voltage from the power supply circuit to the gate terminal of the MCT.

대표청구항 ▼

[ What is claimed is:] [1.] An electric flash apparatus comprising:a power supply circuit including a booster circuit for boosting an output voltage from a power supply battery to positive and negative voltages each having a predetermined value, said booster circuit having at least three output term

[ What is claimed is:] [1.] An electric flash apparatus comprising:a power supply circuit including a booster circuit for boosting an output voltage from a power supply battery to positive and negative voltages each having a predetermined value, said booster circuit having at least three output terminals, said at least three output terminals including a positive voltage output terminal, a negative voltage output terminal and a ground output terminal, a constant voltage element coupled between the positive voltage output terminal and the ground output terminal, and another constant voltage element coupled between the negative voltage output terminal and the ground output terminal, each constant voltage element maintaining a respective predetermined voltage as said positive and negative voltages, respectively;a main capacitor charged by one of the positive and negative voltages boosted by said power supply circuit;a discharge tube through which a discharge current based on a charge built up on said main capacitor flows, thereby performing flash light emission;an MCT (MOS Controlled Thyristor) inserted in a loop of the discharge current from said main capacitor; anda control circuit, including a complementary type push-pull circuit connected to a gate terminal of said MCT, for ON/OFF-controlling said MCT by selectively applying one of the positive and negative voltages from said power supply circuit to the gate terminal of said MCT.